CFD Online Logo CFD Online URL
www.cfd-online.com
[Sponsors]
Home > Forums > OpenFOAM Pre-Processing

Netgen multiple volumes

Register Blogs Members List Search Today's Posts Mark Forums Read

Reply
 
LinkBack Thread Tools Display Modes
Old   February 11, 2005, 12:13
Default HI, I think Netgen is a ve
  #1
Pei-Ying Hsieh (Hsieh)
Guest
 
Posts: n/a
HI,

I think Netgen is a very nice tool for generating Tet elements. However, it only generate 1 volume at a time. If I generate two separate volumes (these two volumes will have common faces), is it possible to combine these two volumes into one volume and then set the common faces as internal bounday conditions?

Another issue with this apporach is that, how to ensure that the points generated on the common faces are the same on both sides so that they can be merged?

Pei
  Reply With Quote

Old   February 11, 2005, 12:25
Default Hello Pei, if netgen does n
  #2
Mattijs Janssens (Mattijs)
Guest
 
Posts: n/a
Hello Pei,

if netgen does not do what you want you could try generating a single mesh and use the splitMesh utility to introduce the cut. splitMesh splits a mesh along internal faces (i.e. creates external faces from internal ones)

1] You will have to generate a 'faceSet' with all of the faces in it. A faceSet can be generated using the faceSet utility.

2] in the polyMesh/boundary file add two zero sized patches at the end.

Now

splitMesh

will try to split your mesh along the faces in the faceSet.

This is all a bit experimental so you might want to try it on a small hex mesh first.

Mattijs
  Reply With Quote

Old   February 11, 2005, 15:44
Default Thanks Mattijs! The purpos
  #3
Pei-Ying Hsieh (Hsieh)
Guest
 
Posts: n/a
Thanks Mattijs!

The purpose of this really is related to gamma initialization. I am hoping to use the cell information (meaning cell numbers) inside specific blocks (volumes) and then initialize all these cells to gamma = 1. Ocassonally, I have to initialize gamma to 1 on irregular geometries.

Pei
  Reply With Quote

Old   February 11, 2005, 16:00
Default You probably have studied the
  #4
Mattijs Janssens (Mattijs)
Guest
 
Posts: n/a
You probably have studied the setGammaDamBreak utility which sets the gamma based on simple geometric info.

If you want it to use the netgen region info you will have to modify the netgenNeutralToFoam converter to read the region information as well and create a labelList with the region for every cell. Write this to a file and modify your setGammaDambreak to read this file and apply it.
  Reply With Quote

Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On


Similar Threads
Thread Thread Starter Forum Replies Last Post
Netgen now on Sourceforge philippose Open Source Meshers: Gmsh, Netgen, CGNS, ... 71 November 13, 2014 08:44
Netgen v45 Release Candidate 2 philippose Open Source Meshers: Gmsh, Netgen, CGNS, ... 2 April 29, 2008 16:58
Netgen and surfacecheck markc Open Source Meshers: Gmsh, Netgen, CGNS, ... 1 March 27, 2008 16:43
Netgen under fedora 5 joegi Open Source Meshers: Gmsh, Netgen, CGNS, ... 1 June 15, 2006 17:04
Netgen useful for CFDproblems nico OpenFOAM Pre-Processing 0 December 14, 2005 04:54


All times are GMT -4. The time now is 06:29.